Air purifier



FIG. 1 is a top front perspective view of an air purifier;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a left side elevation view thereof;

FIG. 5 is a right side elevation view thereof;

FIG. 6 is a top plan view thereof; and

FIG. 7 is a bottom plan view thereof.

FIG. 23 is an exploded top front perspective view thereof, separating an upper piece of the vent cover from a lower piece of the vent cover;

FIG. 24 is an exploded bottom front perspective view thereof, separating an upper piece of the vent cover from a lower piece of the vent cover; and,

FIG. 25 is a cross-sectional view taken along line 25-25 in FIG. 17 .

Broken lines illustrate portions of the air purifier that form no part of the claimed design. 

CLAIM The ornamental design for an air purifier, as shown and described. 